Ebola and Marburg virus outbreak toolbox

Ebola and Marburg virus outbreak toolbox

Updated | August 2024

Welcome to the Ebola and Marburg virus Outbreak toolbox

Key reference documents

Case definitions

WHO suggested outbreak case definition1

Suspected case2

  • any person, alive or dead, suffering or having suffered from sudden onset of high fever, and had contact with:
    • a suspected, probable, or confirmed Ebola case, or a dead or sick animal; OR
  • any person with sudden onset of high fever, AND at least three of the following symptoms: headache, lethargy, anorexia/loss of appetite, aching muscles or joints, stomach pain, difficulty swallowing, vomiting, difficulty breathing, diarrhoea, hiccups; OR
  • any person with inexplicable bleeding; OR
  • any sudden, inexplicable death.
Probable case3

  • any suspected case evaluated by a clinician, OR
  • any deceased suspected case (where it has not been possible to collect specimens for laboratory confirmation) having an epidemiological link with a confirmed case.
Confirmed case3
  • any suspected or probable case with a positive laboratory result (detection of Ebola virus by reverse transcription polymerase chain reaction (RT-PCR), or detection of Immunoglobulin M (IgM) antibodies directed against Ebola viruses).
Discarded case3
  • any suspected or probable case with a negative laboratory result (showing no specific antibodies, ribonucleic acid (RNA) or specific detectable antigens).

WHO surveillance case definition

WHO other definitions

Definition of a contact of a case:

  • Any person having been exposed to a suspected, probable or confirmed case of Ebola virus infection, less than 21 days before the identification as a contact by surveillance teams, in at least one of the following ways:
    • slept in the same household with a case
    • direct physical contact with the case (alive or dead) during the illness
    • direct physical contact with the (dead) case at the funeral
    • touched his/her blood or body fluids during the illness
    • touched his/her clothes or linen
    • been breastfed by a patient (baby).

Dead or sick animal contacts

  • Any person having been exposed to a sick or dead animal, less than 21 days before the identification as a contact by surveillance teams, in at least one of the following ways:
    • direct physical contact with the animal
    • direct contact with the animal’s blood or body fluids
    • carved up the animal
    • eaten raw bush-meat

Laboratory contacts

  • Any person having been exposed to biological material in a laboratory, less than 21 days before the identification as a contact by surveillance teams, in at least one of the following ways:
    • has had direct contact with specimens collected from suspected Ebola patients
    • has had direct contact with specimens collected from suspected Ebola animal cases

Other infection risk factors include contact with a hospital where Ebola cases are being treated; injection or vaccination in the 21 days preceding the onset of symptoms.

  • The contact person should be followed for 21 days after exposure. If the contact person is asymptomatic for 21 days after exposure, they can be released the follow-up

1. See: Case definition recommendations for Ebola or Marburg virus diseases (Geneva: World Health Organization; 2014).

2. Case definition to be used by mobile teams, health stations and health centres. Adapt as needed to new clinical presentations or different modes of transmission related to the local event.

3. Case definitions for exclusive use by hospitals and surveillance teams.

 

Data collection tools

Response tools and resources

Training

  • Ebola: GO 2.0 : (Open WHO courses). 
  • Ebola: Knowledge resources for responders : (Open WHO courses). 
  • Ebola: Clinical management of Ebola virus disease : (Open WHO courses). 
  • Ebola: ePROTECT (an occupational health and safety briefing) (Open WHO courses). 


 

Other resources

One Health resources